How do you convert millimeters to inches?

To convert millimeters to inches, multiply the millimeter value by 0.03937008. For example: 1) 1 mm = 0.03937008 in, 2) 10 mm = 0.3937008 in, 3) 100 mm = 3.937008 in. Our calculator handles this automatically.

What is 1 millimeter equal to in inches?

1 millimeter equals exactly 0.03937008 inches. This is a standard conversion used worldwide in length measurements. For quick estimates, you can think of 1 millimeter as being about 0.04 inches, or 25 millimeters as about 1 inch.

Why would I need to convert millimeters to inches?

Converting millimeters to inches is useful when: 1) Working with tools and materials from different regions, 2) Reading technical drawings or specifications, 3) Converting between metric and imperial units, 4) Working on international projects.

How many millimeters make an inch?

1 inch equals exactly 25.4 millimeters. Conversely, 1 millimeter equals 0.03937008 inches. For quick estimates, you can think of 1 inch as 25 millimeters, or 100 millimeters as about 4 inches.

Millimeters to Inches Conversion Calculator

Millimeter (mm) to Inch (in) Converter

Symbol: mm (millimeters), in (inches)

What they are:

The millimeter is a metric unit of length equal to one thousandth of a meter, while the inch is a unit of length in the imperial and US customary systems, traditionally defined as 1/12 of a foot.

Conversion Facts:

1 millimeter = 0.03937008 inches
1 inch = 25.4 millimeters
10 mm ≈ 0.394 inches
100 mm ≈ 3.937 inches

From:

Millimeter (mm)

To:

Inch (in)

Conversion Result

1 mm=

1.000 in

Use the converter above to calculate different values and units

What are Length Measurements?

Length measurements are fundamental units used to quantify distance, size, and dimensions. Millimeters (mm) and inches (in) are two of the most commonly used units for small-scale measurements in the metric and imperial systems respectively.

The millimeter belongs to the International System of Units (SI) and is precisely defined, while the inch has been standardized internationally as exactly 25.4 millimeters since 1959. This standardization ensures consistent conversions between these systems worldwide.

Common Millimeters to Inches Conversions

Millimeters (mm)	Inches (in)	Common Reference
1	0.039	Thickness of a credit card
5	0.197	Standard pencil diameter
10	0.394	Width of a standard staple
25.4	1	Exact equivalent of 1 inch
50	1.969	Width of a golf ball
100	3.937	Standard photo width
150	5.906	Smartphone width (approx.)
304.8	12	Standard ruler (1 foot)

Practical Use Cases

DIY Projects: Converting measurements between metric and imperial tools, fasteners, and materials
Engineering & Manufacturing: Reading international blueprints and specifications that use different measurement systems
Electronics: Working with component sizes, PCB dimensions, and display sizes often given in millimeters or inches
Crafting & Sewing: Following patterns from different regions that specify dimensions in different units
Medical Applications: Converting between measurement systems for medical devices and imaging
Academic & Scientific Work: Converting measurements for international research and publications

Educational Resource

This educational video explains the relationship between millimeters and inches and demonstrates how to convert between these units with practical examples and applications.

Conversion Tools

Download Conversion Chart (PDF)

Get our comprehensive millimeters to inches conversion chart for quick reference when you're offline.

Millimeters to Inches Conversion FAQs

Find answers to common questions about converting between millimeters and inches.